Summary of Options (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
NUMBER OF SHARES
Options outstanding, beginning balance	5,042,800
Granted	814,300
Exercised	(952,300)
Cancelled	(159,600)
Options outstanding, ending balance	4,745,200
Vested and expected to vest, end of period	4,562,900
Exercisable, end of period	2,582,200
PER SHARE EXERCISE PRICE
Options outstanding, beginning balance	$ 38.56	[1]
Granted	$ 47.81	[1]
Exercised	$ 32.57	[1]
Cancelled	$ 45.61	[1]
Options outstanding, ending balance	$ 41.11	[1]
Vested and expected to vest, end of period	$ 40.92	[1]
Exercisable, end of period	$ 36.46	[1]
REMAINING CONTRACTUAL LIFE IN YEARS
Options outstanding, ending balance	5 years 10 months 24 days	[1]
Vested and expected to vest, end of period	5 years 9 months 18 days	[1]
Exercisable, end of period	3 years 11 months 19 days	[1]
AGGREGATE INTRINSIC VALUE
Options outstanding, ending balance	$ 85.7
Vested and expected to vest, end of period	83.3
Exercisable, end of period	$ 58.6

[1] Weighted Average